Britain's Prime Minister David Cameron speaks during a ceremony at the St. Symphorien Military Cemetery in Mons on Aug 4, 2014. Russia must stop its tanks from entering Ukraine, British Prime Minister David Cameron said on Thursday, warning Moscow it would face further consequences if a political solution to the crisis was not found. -- PHOTO: REUTERS

LONDON (REUTERS) - Russia must stop its tanks from entering Ukraine, British Prime Minister David Cameron said on Thursday, warning Moscow it would face further consequences if a political solution to the crisis was not found.

Ukraine accused Russia on Thursday of bringing troops into the south-east of the country in support of pro-Moscow separatist rebels, two days after the presidents of the two countries held their first talks in more than two months and agreed to work towards launching a peace process.

"It is simply not enough to engage in talks in Minsk, while Russian tanks continue to roll over the border into Ukraine. Such activity must cease immediately," Cameron said in a statement.

"We urge Russia to pursue a different path and to find a political solution to this crisis. If Russia does not, then she should be in no doubt that there will be further consequences."